When you get directions in Google Maps on the desktop, a route is generated which can then be changed by dragging new waypoints into the route. I would like to save this custom route and send it to my phone to navigate via Google Maps navigation on the phone. How can I do this?
Although you can't do exactly what I wanted, I've discovered a way to do something pretty similar.
First, get the directions and the generated route. Next, drag the waypoints into the route. Next, instead of sending to the phone immediately, go through the route, right click on each waypoint in turn, and click "Add a destination". The waypoint will be added to the end of the destinations list; DO NOT reorder this list yet or the other waypoints will be lost.
Once you've added each waypoint as a destination in order, drag the final destination (in the destinations list on the left) to the end. This will have created a route going from your original point A to B, but with the desired waypoints as destinations. When you now "Send directions to your phone", these destinations will be included in the route that Google Maps navigation follows.
Unfortunately, I still haven't found a way to save this list of destinations. That would be ideal. If anyone knows a way, please comment and I'll update this answer to show it.